Organic Light Emitting Diode (OLED) display devices belong to a new type flat panel display device, with such characteristics as lightness, thinness, high brightness, wide color gamut, quick response, etc.
An OLED display panel mainly comprises a substrate, a first electrode formed on the substrate for injecting charges of a first polarity, a second electrode arranged on the first electrode for injecting charges of a second polarity that is opposite to the first polarity, and an organic light emitting layer arranged between the first electrode and the second electrode. When a suitable biasing voltage is applied across the two electrodes, the organic light emitting layer is excited to emit light through injection, transport and recombination of carriers (electrons and holes), thus achieving the object of display.
An existing OLED display device is shown in FIG. 1, primarily comprising a substrate 101, a reflective layer 102, an anode 103, a hole injection layer 104, a hole transport layer 105, a light emitting layer 106, an electron injection layer 107, a buffer layer 108, and a cathode 109. The reflective layer 102 can improve the display brightness of the OLED.
However, the existing OLED display device may either realize a transparent display effect only, i.e. when information is normally displayed, the object behind the display device may be viewed also, or realize an ordinary non-transparent display effect only. That is to say, it is impossible to provide an OLED display device in which transparent display and original non-transparent display are compatible with each other, which brings limitations to the use by users.